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UNITED STATES PATENT OFFICE.

GEORGE H. DIMOND AND VILBUR F. DIAL, OF BRIDGEPORT, CONNECTICUT, ASSIGNORS TO THE VHEELER 8: WILSON MANUFACTURING COMPANY,

OF SAME PLACE.

SEAM-TRIMMING MECHANISM.

SPECIFICATION forming part of Letters Patent No. 568,896, dated October 6, 1896.

i Application iled July 13, 1896. Serial No. 598,973. (No model.)

T all whom, it may concern:

Be it 'known that we, GEoRGE H. DIMOND and VILBUR F. DIAL, of Bridgeport, county of Fairfield, State of Connecticut, have invented an Improvement in Seam-Trimming Mechanism, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representinglike parts.

This invention has for its object to improve and simplify the mechanism employed in trimming parallel to the seam material while being stitched, our improvement being especially applicable for use in connection with very light, thin, and soft material.

Our invention is an improvement on that class of trimmers employing an independent yielding holding device to act on the material and hold it firmly while being cut.

In our invention. we employ a cutter-bar having a knife-block attached thereto and carrying a knife, and for the best results said knife-block is made adjustable laterally to enable it to be placed at the proper position with relation to the needle to thus remove more or less of the material outside of the seam. In connection with this knife and its bar we employ a second independent bar, which actuates a yielding holding device, the

3o latter being entirely disconnected from the knife-block and being also independent of the usual presser foot or roll. This second bar is moved by a lever acted upon by a cam, and by its use the strain on the cutter-bar 3 5 and its wear in its bearings is reduced beyond what it would be if one bar carried both the knife and the holding device, and, further, such construction enables the holding device to be so located out of the way of the opera- 4o tor as to leave the knife easy of access for adjustment.

Our invention consists in a seam-trimming mechanism composed of a reciprocating bar having an attached knife-block and knife, a

second independent bar having an attached yielding holding device cooperating with the knife, and means for reciprocating said bars in the proper time and order to operate substantially as will be described.

Figure l shows in front elevation a sufficient portion of a sewing-machine of wellknown construction with our improvements added to enable our invention to be understood. Fig. 2 is a section of Fig. l in the line a; Fig. 3 shows the yielding holding de- 55 vice enlarged with part of its carrying-bar; Fig. 4, a detail of the lower end of the said bar, and Figs. 5 and 6 show enlarged the knife and parts of its carrying-bar in two different positions.

The bed-plate D, the head A, the Aneedlebar A', its actuating-shaft A3, the knife-carrying bar a', the knife a, the cam E on the shaft A3, the lever b for moving the knife-bar, the arm d, actuated by said cam and adapted to be coupled to an arm of said lever, are and may be all substantially as in our Patent No. 540,907, dated June ll, 1895, where the parts abovereferred to are designated by the same letters. The needle ax is connected to Ithe 7o needle-bar in usual manner. f

The cutter-block a5, located in a hole in the usual needle-hole plate, and the spring a6 to act upon and keep said block pressed toward the line in which the knife reciprocates, so as to form an opposed member to cooperate with the edge d10 of the knife in completing the cut, are and may be all as common in other sewing-machines. Herein the knife a is attached by screws f to a knife-block C013, 8o attached to the knife-bar by a screw am.

IVe have arranged in the head of the machine, in front of the knife-carrying bar a,

a second independent bar e, which carries and actuates the yielding holding device, it consisting, essentially, of an arm e', depending from a slide e3, shown as applied to the lower end of the bar e loosely, so as to slide or yield with relation thereto, as necessity requires, we having placed a spring e6, between 9o the down-stop e4 and the up-stop e5, fast on the bar e, said spring acting to hold the lower end of said slide against the down-stop e4.

As the bar e descends the holder e meets the i work near the line where it is to be cut and 9 5, is arrested in its descent, while the bar e continues its descent, moving in said slide and compressing the spring e6, the said holding device thus holding firmly, but with a yielding pressure, the material close to the point roo the lever b, so that said lever becomes the actuator for said bar c.

By placing the bar e in front of the bar d the screws j', used to connect the knife to the block 61,13, or it may be to the bar itself, are left fully exposed and of easy access to the operator when the knife is to be changed or adjusted up or down, and by employing an entirely independent bar for the yielding vholding device it is possible to relieve the knife-bar a of very much strain and Wear.

If desired, the bolt es may be Withdrawn and the holding device be put out of action, leaving the knife in condition to be used.

The presser-bar D and its roller foot or presser are and maybe of usual construction.

Having described our invention, what we claim as new, and desire to secure by Letters Patent, is-

l. A seam-trimming mechanism, composed of a cutter-block, a reciprocating bar having an attached knife, a second bar having an attached independent yielding holding device coperating With the knife, and means c011- nected with and for reciprocating both of said bars in the proper time and order, to operate, substantially as described.

2. A knife-bar, an attached knife, a second bar arranged parallel to the same, a holding device mounted loosely on said second bar, a spring interposed between said holdingr device and said bar, a rotating shaft, and a cam 4o thereon, combined with a lever connected directly with both said bars whereby they are operated, substantially as described.

3. In a seam-trimming mechanism, a knifebar, an adjustable knife-block attached there- 45 to and a knife mounted on said block, combined with a second bar having an attached independent yielding holding device coperating With said knife, means connected WithV and for reciprocating both of said bars in the 5o proper time and order, a needle-hole plate and a cutter-block to operate, substantially as described.

In testimony whereof We have signed our names to this specification in the presence of 55 two subscribing witnesses.

GEORGE H. DIMOND. WILBUR F. DIAL. Witnesses IsAAc HOLDEN, B. C. HAMILTON. 

